At present, examples of piezoelectric resonator devices include crystal oscillators, crystal resonators, and the like. Such a piezoelectric resonator device has a housing formed of a rectangular parallelepiped package. The package comprises a base and a lid. In the package, a piezoelectric resonator plate is held and bonded with the base using a conductive adhesive. By bonding the base with the lid, the piezoelectric resonator plate is hermetically enclosed in the package (see, for example, Patent Document 1 below).    Patent Document 1: JP 2005-191709A